CVE-2025-13836

HIGH

Python < 3.13.11 - Denial of Service

Title source: rule
STIX 2.1

Description

When reading an HTTP response from a server, if no read amount is specified, the default behavior will be to use Content-Length. This allows a malicious server to cause the client to read large amounts of data into memory, potentially causing OOM or other DoS.

References (9)

Core 9
Core References
Issue Tracking, Patch issue-tracking
https://github.com/python/cpython/issues/119451
Issue Tracking, Patch patch
https://github.com/python/cpython/pull/119454

Scores

CVSS v3 7.5
EPSS 0.0010
EPSS Percentile 26.5%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-400
Status published
Products (3)
python/python 3.14.0
python/python 3.15.0 alpha1 (2 CPE variants)
python/python < 3.13.11
Published Dec 01, 2025
Tracked Since Feb 18, 2026